The present invention relates to an image processing system, a projector, a program, an information storage medium, and an image processing method capable of detecting a change in the relative position between a projection target and a projector based on sensing information.
In recent years, a projector including a CCD camera has been proposed which projects an image onto a projection target such as a screen, senses the projected image by using the CCD camera, and performs calibration processing such as image distortion correction.
However, such a projector cannot display an appropriate image when the relative position between the projector and the screen is changed after calibration processing, such as when the user accidentally collides with the projector or when the user hits the screen using a pointer.
In this case, since the user believes that an appropriate image is displayed by the calibration processing, the user may not become aware that an appropriate image is not displayed.
In order to solve such a problem, the projector must detect a change in the relative position between the projector and the screen.
JP-A-2001-109422 discloses a projector which stores sensing data obtained by using a CCD camera in a frame memory and detects the movement of the image from a change in the content of the frame memory.
An ordinary movement detection method using a camera detects movement by comparing sensing data at a time “t” stored in a memory with sensing data at a time “t+1”.
However, since an ordinary movement detection method requires that sensing data before one time unit be stored, the memory utilization efficiency is decreased. Moreover, the sensing data comparison processing is complicated.
Moreover, even if the user has become aware that the relative position between the projector and the screen has changed, the projector must again perform the calibration processing.